Equalizer link for multiple branch slings



April 27, 1954 0. w. GRAZIER 2,676,834

EQUALIZER LINK FOR MULTIPLE BRANCH SLINGS Filed May 2, 1951 FIG. 4

INVENTOR DORE w. GRAZIER N BY g ufixwa ATTORNEY Patented Apr. 27, 1954EQUALIZER LINK FOR MULTIPLE BRANCH SLINGS Dor W. Grazier, Johnstow-n,Pin,- a'sslgnor to United States Steel Corporatlom'a. corporation of NewJersey Application May 2, 1951, SeriaIN'mZZL HI 2 Claims. (Cl. 2941-474;

This invention relates to an equalizer joiner link for lift cranes andthe like.

In industry a great number of loads handled by overhead traveling cranesare lifted and carried by means of slings, each branch or leg of whichis equipped with a hook or similar device for attaching to the load. Upto the time of my invention, in the most commonly used form" of 4-branchslings, a large center link was supported by the crane hook and carriedtwo smaller links, generally known as master joiner links. To each ofthe smaller links were attached two of the sling chains or ropes whichwere spread out as required for attachment to the load. The use of thisform of rig was a constant source of trouble for both maintenance andoperating personnel, since there was nothing in the rig to compensatefor variations in the length of the branches. This trouble occurredfrequently since it is practically impossible to keep all four legs of asling at exactly the same length. Even a slight difierence in the lengthof one of the branches, or in the shape of the hooks or in the distanceof the attachment points of the load from the center of gravity lineresulted in half of the total load being imposed on a single branchand/or in undesirable twisting of the load.

It is an object of this invention to provide a master joiner link whichadjusts itself automatically in two different planes and. distributesthe load evenly over all branches of the sling.

This and other objects will become apparent after referring to thefollowing specification and attached drawings, in which:

Figure 1 is an elevational view showing a 4- branch sling provided withthe equalizer link of the present invention;

Figure 2 is an enlarged detail view of the upper portion of the slingshown in Figure 1;

Figure 3 is a plan view of the equalizer link; and

Figure 4 is a cross-sectional view taken on the line IVIV of Figure 3.

Referring more particularly to the drawings, reference numeral 2indicates the hook of a lift crane (not shown) supporting connectinglink 4, the walls of which are substantially arcuate in cross section. Apair of equalizing links 6 are carried by the connecting link 4. Each ofthe links 6 is provided with two end openings 8 on either side of thecenter opening Ill. The walls of the equalizing link 6 are substantiallyround in, cross section. The body of the link is elongated as best shownin Figure 3. The dimeter of the center opening II) is substantiallylarger than the outside diameter of the wall of the connecting link 4 soas to provide point contact between the equalizing link and theconnecting link. Two legs l2 are supported by each of the links 6 tothis purpose. Each of the legs I2 is provided with an eye l4 at itsupper end, the rope of the eye being received in the opening 6. A hookit at the bottom of each of the legs [2 is attached to and supports theload L.

In use in a 4-branch sling, as shown in Figures 1 and 2, the equalizerlinks 6 take the place of the two master joiner links which wereformerly used. By this arrangement the links 6 function not only asjoiner links, but also as balance levers which distribute the loadevenly. The rounded cross sectional construction of the link, as bestshown in Figure 4, provides point contact so that equalization of theload results automatically, regardless of variations in lengths of thebranches. By thus equalizing the strain on the branches and hooks,breakage of these parts is reduced to a minimum and consequently thehazards to personnel working in the vicinity of the crane are reduced toa minimum. Also, where twisting or distortion is likely to result indamage to the load being handled, as for example in assembly work,foundries, etc., such damages are eliminated by the use of my inventionwithout in any way altering the existing practice or technique.

It will be noted that the use of the equalizer link of my invention isnot limited to slings having any specific number of branches or to anyparticular arrangement of links which may be employed to form varioustypes of slings or tension rigs. The equalizer link may b used eithersingly or in multiples, with common or interconnected mountings toprovide for equal distribution of tension.

While one embodiment of my invention has been shown and described itwill be apparent that other adaptations and modifications may be madewithout departing from the scope of the following claims.

I claim:

1. Load-supporting apparatus comprising a load-carrying member, a centerlink supported by said load-carrying member, the walls of said centerlink being arcuate in cross section, a joiner link being elongated inshape and having three spaced apart openings in alignment therein, saidcenter opening having a diameter substantially greater than the crosssection of said center link, said joiner linkbeing mounted Q11 Saidcenter link by its center opening. a two branch flexible load-supportingmember received in each of said outside openings and carried by saidjoiner link, said outside openings each having a diameter substantiallygreater than the cross section of the load-supporting member receivedtherein, the walls of said joiner link being arcuate in cross section,said flexible members being the only loadsupporting members attached tosaid link.

2. Load-supporting apparatus comprising a load-carrying member, a centerlink supported by said load-carrying member, the walls of said centerlink being arcuate in'cross section, a pair of joiner links carried bysaid center link, each of said joiner links being elongated in shape andhaving three spaced apart openings in alignment therein, the centeropening in each joiner link receiving said center link and having adiameter substantially greater than the cross section of said centerlink, a single branch flexible loadsupporting member received in each ofsaid outside openings and carried by said joiner links, said outsideopenings each having a diameter substantially greater than the crosssection of the load-supporting member received therein, the walls ofsaid joiner links being arcuate in cross section, said flexible membersbeing the only load-supporting members attached to said links.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 551,836 Provan Dec. 24, 1895 ,326,969 Rounds Jan. 6, 19201,722,329 Grindahl et a1 July 30, 1929 OTHER REFERENCES Ford Field forJuly 1949, published by H. A. Apple (Lift Kit), page 50 relied on. (Copyin Scientific Library and Division 34.)

